摘要
A broadband （- 176 nm, R 〉 98%, λo = 800 nm） and high laser-induced damage threshold （LIDT = 2.4 J/cm^2） TiO2/HfO2/SiO2 high reflector （HR） for Ti：sapphire chirped-pulse amplification （CPA） laser system is fabricated by the electron beam evaporation. The refractive index and extinction coefficient of TiO2 and HfO2 films are calculated from single-layer films＇ transmittance spectra. The properties of HR are mainly determined by the high refractive index material. The high refractive index leads to wide bandwidth. A low extinction coefficient indicates low absorption and high LIDT. The possible damage mechanism of HR is discussed.
A broadband （- 176 nm, R 〉 98%, λo = 800 nm） and high laser-induced damage threshold （LIDT = 2.4 J/cm^2） TiO2/HfO2/SiO2 high reflector （HR） for Ti：sapphire chirped-pulse amplification （CPA） laser system is fabricated by the electron beam evaporation. The refractive index and extinction coefficient of TiO2 and HfO2 films are calculated from single-layer films＇ transmittance spectra. The properties of HR are mainly determined by the high refractive index material. The high refractive index leads to wide bandwidth. A low extinction coefficient indicates low absorption and high LIDT. The possible damage mechanism of HR is discussed.
基金
This work was supported by the National Natural Science Foundation of China under Grant No.60608020.
